The topic of “illegal” immigration has been a major aspect of public discourse in the United States and many other immigrant-receiving countries. From the beginning of its modern invocation in the early twentieth century, the often ill-defined epithet of human “illegality” has figured prominently in the media; in vigorous public debates at the national, state, and local levels; and in presidential campaigns. In this collection of essays, contributors from a variety of disciplines – anthropology, law, political science, religious studies, and sociology – examine how immigration law shapes immigrant illegality, how the concept of immigrant illegality is deployed and lived, and how its power is wielded and resisted. The authors conclude that the current concept of immigrant illegality is in need of sustained critique, as careful analysis will aid policy discussions and lead to more just solutions.